Sheet processing method



July 4, 1967 D. B. SEELEY SHEET PROCESSING METHOD 2 Sheets-Sheet 1 Filed March 29, 1963 mm mm INVENTOR. Du/W/HM B. SEE/.EY BY HTTORNEY July 4, 1967 D. B. SEELEY 3,329,756

SHEET PROCESS ING METHOD Filed March 29, 1963 2 Sheets-Sheet 2 INVENTOR.

. HTTOR/VEI United States Patent 3,329,756 SHEET PROCESSING METHGD Dunham B. Seeley, Fairport, N.Y., assignor to Burroughs Corporation, Detroit, Mich, a corporation of Michigan Filed Mar. 29, 1963, Ser. No. 268,871 5 Claims. (Cl. 264231) The present invent-ion relates to sheet processing method, and particularly to such methods for setting (i.e., making relatively permanent) a temporarily flattened or bent formation in the sheet. The invention is particularly herein described, purely for illustrative purposes, wit-h respect to applying stripes of magnetic material onto a sheet member and then flattening the sheet, using apparatus described in my co-pending application Ser. No. 268,872, filed Mar. 29, 1963.

Magnetically striped paper sheets have heretofore been used as record media, the magnetic stripes being utilized for magnetically storing data read into and out of the paper sheet from a machine. Such striped sheets are commonly produced in a continuous manner utilizing waterbase magnetic ink compositions, such as disclosed in Colwill et al., US. Patent No. 3,023,123, in Colwill US. patent application Ser. No. 259,042, filed Feb. 18, 1963, or in my co-pending application Ser No. 268,872, filed Mar. 29, 1963. As described in the latter patent application, when the water-base magnetic ink composition is applied as a stripe on the paper, a V-bend formation is formed in the paper because of the swelling of the paper fibers. This V-bend formation, in turn, produces a tendency to form wrinkles and folds in the paper as it is processed through the apparatus, particularly when high speed apparatus is used. The apparatus described in my co-pending application Ser. No. 268,872, filed Mar. 29, 1963, provides means for substantially reducing or completely eliminating the formation of the wrinkles or folds, but as stated there, the V-bends produced by the swelling of the paper fibers still tend to remain. In many applications, this V-bend is not particularly troublesome, but in some applications, it is desirable to remove also these V-bends so that the striped paper will be and remain substantially flat.

A broad object of the present invention is to provide a method for relatively permanently setting a sheet of paper or other similar fibrous material into a flattened or other desired configuration.

A more specific object of the invention is to provide a method for relatively permanently setting in a flattened or other desired configuration, a sheet having a coating or stripe of a material, such as magnetic ink, which includes a synthetic resin.

A further object of the invention is to provide a method for producing striped sheets, which not only substantially reduces or completely eliminates the formation of the wrinkles referred to above, but also flattens the sheet and sets the sheet permanently in its flattened configuration.

By the expression permanent and/or setting, in the context of this disclosure, it is meant that the sheet by itself, i.e., when not subjected to extraneous influences, does not exhibit a tendency to return to its initial form. However, it is to be understood that the sheet could be returned to its initial form, or re-set to another form, by the same means used for setting it from its initial form, or by other means.

In accordance with one aspect of the invention, a method is provided comprising temporarily forming a sheet of fibrous material into a desired configuration, and then subjecting said fibrous material, while dry and exposed to the air or a gaseous atmosphere, to heat to set same in said desired configuration.

In accordance with a further aspect of the invention, the above method is performed with respect to a paper sheet.

In accordance with another aspect of the invention, there is provided apparatus comprising means for temporarily forming a sheet of fibrous material into a desired configuration, and means for subjecting said fibrous material, while dry and exposed to the air or a gaseous atmosphere, to heat to set same in said desired configuration.

While the invention is particularly applicable for permanently flattening a sheet, it will be appreciated that the invention could also be used for setting the sheet in other configurations, such as in forming folds in the sheet.

These and other aspects of the invention will become apparent from the following description of preferred embodiments thereof.

In the drawings:

FIG. 1 is a diagram of an apparatus constructed in accordance with the invention for applying stripes of magnetic material onto a paper sheet member;

FIG. 2a, taken at line 2a-2a of FIG. 1, depicts (with some exaggeration for purposes of clarity) how the paper is first formed with a V-bend or concavity along the line receiving the magnetic ink stripe, this formation being caused by the swelling of the paper due to the water in the magnetic ink;

FIG. 2b, taken at line 2b2b of FIG. 1, depicts (also with some exaggeration for purposes of clarity) how the paper normally appears after it is dried, showing the V- bend extending in the opposite direction;

FIG. 20, taken at line 2c2c of FIG. 1, depicts how the paper appears after it issues from the apparatus wherein it has been flattened and permanently set in its flattened condition;

FIG. 3 illustrates prior apparatus using a conventional roll, to show how the V-bend formation in the paper would tend to produce a Wrinkle or fold in the paper as it passes over the roll, the wrinkle illustrated also being somewhat exaggerated for purposes of clarity;

FIG. 4 illustrates similar apparatus as in FIG. 3, except utilizing the novel roll structure (hereinafter called an anti-wrinkler roll) which prevents or substantially reduces the formation of wrinkles or folds;

FIG. 5 is a perspective view of an anti-Wrinkler roll of FIG. 4;

FIG. 6 is is a perspective view of the heating unit utilized in the apparatus of FIG. 1 for setting the paper in its flattened condition;

FIG. 7a illustrates another embodiment of the invention for setting the paper in a folded condition rather than in a flattened condition; and

FIG. 7b illustrates the paper permanently set in the folded condition as produced by the embodiment of FIG. 7a.

The apparatus illustrated in FIG. 1 is similar to that described in my co-pending application Ser. No. 268,872, filed Mar. 29, 1963. The sheet member to be processed, which in this case is a paper web 10 to be striped with magnetic material 11 (FIGS. 2a and 2b), is driven from a supply roll 12 at the input side of the apparatus to pass between a striping applicator 14 and an anvil 16,

Applicator 14 applies a magnetic stripe (or a plurality of such stripes) to the paper web, and may be of a construction similar to that disclosed in co-pending application of Colwill U.S. Ser. No. 259,042 filed Feb. 18, 1963.

The magnetic striping material is a liquid magnetic ink, a preferred composition being one which includes magnetic particles dispersed in an aqueous medium and including a synthetic latex. Following is an example of a material which can be used:

When the water is evaporated and the composition dried, it produces magnetic stripes free of tack and resistant to blocking and smudging under dry and humid conditions.

From the applicator 14, the paper web passes over a pair of idler rolls 18 and 20 which are grooved (not shown) to accommodate the applied stripe, and then to a second pair of idler rolls 22 and 23 to the drying means for drying the liquid stripes. In this case, the drying means is a hot air oven 24 utilizing quartz tube radiant heaters 25 focused on the stripe of liquid material 11 applied by applicator 14.

When the liquid magnetic ink 11 is applied to the paper and as it enters the oven 24 (lines 2a-2a, FIG. 1), the

paper first assumes a V-bend or concavity formation V as shown in FIG. 2a. This is because the Water in the liquid ink swells the paper fibers at the surface receiving the ink, and causes paper to expand at this surface and thereby to form the V-bend formation. As the paper passes through the drying oven 24, the top surface of the paper tends to dry first, causing the fibers at the bottom surface to expand more than those at the top surface, producing a V-bend V in the opposite direction in the paper as shown in FIG. 2b, with the magnetic deposit 11 on the top surface. This is the form the paper is in when it exits from oven 24 (lines 2b-2b, FIG. 1).

In prior art installations as illustrated in FIG. 3, the drying oven utilized conventional rolls having relatively smooth surfaces. As the paper 10' (formed with the V-bend V of FIG. 2a or FIG. 2b, depending upon the drying stage the roll was located in the oven) passed over the roll in the oven (identified as 30 in FIG. 3), there was a tendency to form a longitudinal wrinkle or fold W in the paper in the area of the V-bend V and magnetic stripe 11. This tendency was especially strong in apparatus operating at high speed.

The apparatus of my co-pending application Ser. No. 268,872, filed Mar. 29, 1963 substantially reduces or completely eliminates the tendency to form these wrinkles or folds W, by including in the heating oven 24 specially constructed rolls as illustrated in FIG. 4 and as generally identified by the reference numeral 30, which rolls are herein referred to as anti-wrinkler rolls. The apparatus illustrated utilizes a number of such rolls, each roll being of the same construction as will be described below.

In the illustrated apparatus, the paper web 10, as it enters the oven 24, passes one side of a line 26 of the radiant heaters 25, over one of these anti-wrinkler rolls 30-1 to another idler roll 32, over a second anti-wrinkler roll 30-2, and then past the other side of the line 26 of radiant heaters 25 to a third anti-wrinkler roll 30-3. It then moves past another line 28 of radiant heaters 25 to a fourth anti-wrinkler roll 30-4, from there to an idler roll 34, to a fifth anti-Wrinkler roll 30-5, and past the other side of the heater line 28. It then exits from the oven completely dried and formed with the V-bend as shown in FIG. 2b.

The structure of the five anti-wrinkler rolls 30-1 to 30-5 tandernly arranged in the drying oven 24 is the same in each case and is more fully illustrated in FIG. 5. This embodiment of anti-wrinkler roll includes a central shaft carrying a pair of circular end plates 62 and 64, each mounted on roller bearings 66 so as to be freely rotatable on shaft 60. Along the outer peripheral surface of end plates 62 and 64, there are secured a plurality of rods 70 each fastened to the pair of end plates by bolts 72 and pinned so as to be non-rotatable by pins 73. Each of the rods 70 is transversely grooved at 70 to accommodate the striped area of the Web 10.

Rods 70 form the anti-wrinkler roll peripheral surface which is engageable with the paper web. The outer surfaces of these rods which actually engage the web define a plurality of separate short are surfaces disposed around the circumference of the 'anti-wrinkler roll with each are surface separated by a low area in the form of a depression 71 extending parallel to the longitudinal axis of the roll. The roll is rotatably mounted transverse to the path of the web so that these surfaces of rods 70, i.e., the short arc surfaces of the roll, are successively engaged with the web as the web is driven through the apparatus.

It has been found that the use of the anti-wrinkler rolls 30-1 to 30-5 substantially reduces or completely eliminates the formation of the wrinkles or folds W discussed above produced in prior devices because of the presence of the V-bend formations V in the paper. It is not known with certainty exactly how this anti-wrinkling effect is produced by the use of these rolls. There are probably several factors contributing to this result. First, the short are surfaces produced by rods 70 reduces the peripheral surface engageable with the paper web and thereby permits the paper to slip, and further, gives it room to slip, as it passes over these surfaces. Also, this configuration of the anti-wrinkling roll produces vibrations as the paper web passes over it, and thereby causes the paper to shake itself out.

It is preferable to have an odd number of rods 70, nine being illustrated in the described apparatus, to provide an odd number of the short are surfaces produced by these rods. With the use of an odd number of rods, when the paper web is in contact with a rod at one side of the roll it will be out of contact with a rod at the diametrically opposed point. It has been found that this arrangement minimizes the tendency of the paper to stretch as it passes over the roll, and also probably contributes to the anti- .Wrinkling efiect discussed above.

It will be appreciated that the striped sheet leaving the oven 24 will appear as illustrated in FIG. 2b, that is with the V-bend formation at the striped area, the wrinkles or folds corresponding to W of FIG. 3 having been eliminated or at least substantially reduced by the anti-wrinkler rolls 30-1 to 30-5. With respect to the V-bends, however, while they may have been temporarily flattened as the sheet passes over various rolls in the oven, they will not have been permanently flattened and therefore they will still be present when the sheet leaves oven 24, as shown in FIG. 2b. The present invention is directed to the means for flattening these V-bends and permanently setting them in their flattened condition, so that the striped sheet will appear as illustrated in FIG. 20 when 'it leaves the illustrated apparatus.

For purposes of permanently removing the V-bends as the paper web leaves the drying oven 24, it passes over a pair of rolls 36 and 38 (the latter being grooved, not shown, to accommodate the applied stripe), to a specially-provided unit 40, hereinafter called the setting unit. The structure of unit 40 is shown in FIG. 6 and will be described below in more detail. Briefly, it includes a plu rality of gas burners to provide an intense heat. However, its purpose is not to dry the striped-coating, as the coating is completely dry when it leaves the drying oven 24. Rather, the purpose of setting" unit 40 is to subject the sheet, while it is temporarily flattened and while it is dry and exposed to the air or a gaseous atmosphere, to suificient heat to set it in its flattened condition.

As shown in FIG. 6, setting unit 40 comprises a series of gas burners 100, such as propane torches, disposed to heat the striped paper as it isdriven at high speed through the apparatus. There are fifteen of such gas burners illustrated in FIG. 6, these fifteen being divided into three groups of five burners each. The first group is mounted on a first supporting member 102, the second group of five is mounted on a second supporting member 104, and the third group is mounted on a third supporting member 106. All three groups are carried by a carrier bar 108 secured to the back side of a carrier block 110. The latter block 110 is slideably supported by means of its extension 112 being movably seated in a channel member 114 secured to the apparatus frame structure 116. This arrangement permits the block 110, and therefore the burners 100, to be moved transversely of the paper web so that the burners can be directed against any selected area of the web.

The means for moving or adjusting the burners comprise a screw 118 threaded at one end in block 110, the screw passing at its other end through an inturned extension 120 formed in channel member 114. The latter end of the screw carries an adjusting wheel 122 which permits the screw to be rotated and thereby the block and the burners 100 to be moved transversely of the paper web.

The burners 100 are supplied through conduit 124 having a connection 126, 128 and 130, respectively, to each of the three groups of burners. An adjusting knob 132, 134 and 136, respectively, is provided for each of these connections to adjust the amount of gas supplied to the burners. The burners may be individually adjusted by another adjusting knob 140 supplied for each burner. The foregoing conduit and connections are all carried by carrier bar 108, so that they also move with the burners when the latter are moved transversely of the paper web by manipulation of wheel 122.

As the paper web leaves the drying oven 24, the web being in the configuration illustrated in FIG. 2b with the inverted V-bend V, it is tautly held between rolls 38 and 42 so that the V-bend is temporarily flattened. Setting unit 40 subjects this temporarily flattened area of the web to the intense heat. Best results are obtained when the paper sheet is heated to a point just below its decomposition temperature. In the apparatus illustrated, the paper moves at a high rate of speed, in the order of 400 ft. per minute, and frequently higher, and therefore the full heat of the fifteen burners will not ignite or char the paper. It will be noted that the paper in this area is dry and is exposed to the air or a gaseous atmosphere. This setting of the paper is therefore to be distinguished from the old and common technique of setting by heat and pressure, such as when a steam iron is used.

As the paper leaves the setting unit 40, it passes over a chill roll 42 which cools the heated paper as it is maintained in its flattened condition. Chill roll 42 is followed by another roll 43 which serves to increase the surface of wrap of the paper web around chill roll 42. The paper then passes around rolls 44 and 45 to a calender unit 46 comprising a pair of revolving cylinders 48 and 50 which press the coated stripe into the paper and also smooth down the paper. Next, the paper web passes through a sheeter unit 52 comprising a first roll 54 carrying a cutter blade 56, and a second roll 58, this unit cutting the paper web into individually magnetically striped sheets.

FIG. 2c illustrates the paper in the condition at the stage of the apparatus taken at lines 2c2c of FIG. 1, that is after it passes through the setting unit 40 and the succeeding rolls 42-45. As shown in FIG. 20, the V-bend in the paper sheet has been removed, and the paper appears in its flattened condition which was made permanent by the setting unit 40. At first it was thought that this setting was caused by the melting and then the resolidifying of he synthetic resin material in the latex of the magnetic striping ink. However, it was found that this setting effect is also produced when there are no magnetic stripes, or any other coating material, on the paper, that is when the intense heat is directed to the bare paper. For example, applicant has found that if the paper is temporarily shaped from an initial form to a desired form, it will normally attempt to return to its initial form. However, if while in the temporary desired form it is subjected to the heat of the setting unit 40, it will set or permanently retain the said desired form.

This is more clearly illustrated in FIGS. 7a and 7b idepicting a further embodiment of the invention. In this embodiment, the paper 210 is formed with a fold line 212 about a former member 214, and is subjected to the intense heat of a setting unit 240, comprising a plurality of burners 200. The paper may be held stationary while it is being heated, or 'could be moving parallel to the longitudinal axis of its former member 214. After the paper has cooled, it was found that the fold 212 is permanently set in the paper, and that the paper will not tend to return to its initial form unless it is folded or otherwise re-set to that form. Thus, it will be apparent that the invention can be applied not only to permanently flattening the sheet, but also to permanently setting the sheet into a folded or other desired configuration.

While there has been illustrated and described several embodiments of the invention, it is to be understood that these are illustrative only, and that various features of the invention, alone or in combination, may be used in other embodiments and applications.

I claim:

1. A method for removing a deformation from a dry web of fibrous material moving at a high speed comprising the steps of:

flattening at least the portion of said deformation moving past a selected position in the path of said web by tension applied parallel to the plane of said flattened web portion, and

setting said portion of said deformation in the flattened state by radiantly heating the portion of said web moving past said selected position in the area of said deformation.

2. The method of claim 1 comprising the further step of chilling said web after it has been heated, while it is retained in the flattened configuration.

3. The method of claim 1 in which, during the setting of said deformation, said web is heated to a temperature just below its decomposition temperature of the fibrous material.

4. A method for removing a longitudinal defromation from a dry paper web moving at a high speed, said deformation having been caused by the application of a stripe of coating material in liquid form to said web, comprising the steps of:

flattening by tension, the portion of said web moving past a selected position in the path of said web, said tension being applied parallel to the plane of said flattened web portion and setting said portion of said web in the flattened state by 8 intensely, radiantly heating, to slightly below the de- References Cited composition temperature, said portion of said web UNITED STATES PATENTS in the area of said deformation. 5. A method for removing a deformation from a sheet 1,469,048 9/1923 Nelson X of fibrous material comprising the steps of: 5 1,773,642 7/1930 Roberts 34-66 3,023,123 2/1962 Colwill et al. 117-44 smoothing said sheet of fibrous material while dry by tension applied tangent to said sheet, and setting said sheet in said smooth state by radiantly ROBERT F. WHITE, Primary Examiner.

heating said sheet in the area of said defromation while said sheet is under said tension. 10 HALL, Assistant Examiner- 

1. A METHOD FOR REMOVING A DEFORMATION FROM A DRY WEB OF FIBROUS MATERIAL MOVING AT A HIGH SPEED COMPRISING THE STEPS OF: FLATTENING AT LEAST THE PORTION OF SAID DEFORMATION MOVING PAST A SELECTED POSITION IN THE PATH OF SAID WEB BY TENSION APPLIED PARALLEL TO THE PLANE OF SAID FLATTENED WEB PORTION, AND SETTING SAID PORTION OF SAID DEFORMATION IN THE FLATTENED STATE BY RADIANTLY HEATNG THE PORTION OF SAID WEB MOVING PAST SAID SELECTED POSITION IN THE AREA OF SAID DEFORMATION. 